* In their previous six Europa League campaigns, PAOK have progressed from the group stage on four occasions (2010-11, 2011-12, 2013-14, 2016-17), but were eliminated at the Last 32 stage on each of those occasions.

* Chelsea won the UEFA Europa League in their last appearance in the competition (2012-13), defeating Benfica 2-1 in the final.

* Chelsea boss Maurizio Sarri has a 100 percent win ratio in the group stages matches of the UEFA Europa League, winning all six matches whilst in charge of Napoli in 2015-16.